Apparatus for low temperature carbonization



July 24, 1934. A. TRAUT APPARATUS FOR LOW TEMPERATURE CARBONIZATION 1929 3 Sheets-Sheet 1 Filed Jan. 18

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APPARATUS FOR LOW TEMPERATURE CARBONIZATION Filed Jan. 18 1929 3 Sheets-Sheet 2 Fi Zj vwemboz July 24, 1934. A. TRAUT 1,967,691

APPARATUS FOR LOW TEMPERATURE CARBONIZATION *"Fiiaed Jan. 18. 1929 3 Sheets-Sheet s awuwntoz fl cYoZf TM. a? @7165 Hume/1 with devices for Patented July 24, 1934 I UNITED STATES PATENT OFFICE APPARATUS FOR LOW TEIHPERATURE CARBONIZATION Application January 18, 1929, Serial No. 333,464

InG

ermany February 10, 1928 6 Claims. (01. 202-104) This invention relates to a process and apparatus for the heat treatment of solid, and especially bituminous substances by low-temperature carbonization.

In many examples of the known low-temperature carbonization process, the actual carbonizing chamber, or its internal arrangements, are set in motion, in order to carry the charge forward. The chamber is rotated, for example, about its own axis in a horizontal, inclined or vertical plane, and use is also made of trough, belt or jig conveyors, trucks, revolving discs and the like in order to carry the charge through the chamber. In practice, low-temperature carbonization plants of this type can only be made in the form of a single chamber with restricted capacity and are very expensive, and in addition, the consumption of power for moving the charge is very high, the wear on the material of the chamber is very heavy, and finally the chamber gas is contaminated with dust as the result of the continuous mechanical movement of the charge.

I have now found that these objections can be overcome by allowing the charge of coarse-grained bituminous material to slide down through heated pipes or retorts, mounted at such an angle that the charge travels automatically and provided preventing the charge from completely filling the pipes or retorts thus leaving a free space in said retorts above the charge. A plurality of retortsor lengths of pipe is arranged in series, and preferably in zig-zag formation, being connected together in such a way that the carbonization gas is drawn off without being obliged to pass through the charge. In order to regulate the depth of the charge, suitable baflles, for example, may also be provided in the spaces connecting the pipes or retorts, and any convenient number of such baflles may also be provided in the pipes or retorts themselves. The best method of shutting off the interior of the pipes or retorts from the outside is by means of the .fresh or spent charge of material itself. The new lowtemperature carbonization process can be carried on in a continuous manner, and enables the operation to be performed on a large scale, on the same principle as the working of coke ovens, for example by disposing several groups of serially arranged retorts, heated in common, in brick-work chambers, and combining a plurality of such chambers to form a battery.

The heating is preferably carried out indirectly by means of hot combustion gases, which may be passed in circulation, the heat given off by the gases, being replaced by a source of heat arranged in the circulation.

A low-temperature carbonization plant oper-' ated in accordance with the present invention, will now be described with reference to the accompanying drawings showing apparatus in vertical cross-section and elevation in Figures 1 and 2 and details drawn to a larger scale in Figures 3 and 4 for carrying this invention into effect, but the invention is not restricted to the plant herein illustrated.

The plant consists of a carbonizing chamber proper 1, traversed by heating flues and enclosing retorts 2, disposed serially in zig-zag formation and mounted on water-cooled pipes 6. A carbonizing unit may contain, for example, 4 to 8 such retort columns, and a plurality of such chambers may be disposed in series to form large units. On to each carbonizing chamber is built a heating chamber, consisting of the combustion chamber 5 and a mixing chamber 7. The efiluent gases of combustion are drawn off at 8 through a by-pass 9 and the blower 10, and are blown back into the unit by the mixing chamber '7 which is of the injector type. The surplus gas in circulation may be led away through the pipe 3. Gas burners 11 burn the combustible gas completely without any substantial excess of oxygen and with the production of the highest possible temperatures in the combustion chamber 5, and the said gas is mixed with the circulation gas by means of the nozzles 12 leading to the mixing chamber -7, so as to produce the desired-temperature. The charge runs from the bunker 13 into the charging hoppers 14, and owing to the oblique mounting of the retort, slides down automatically through the retort column to the outlet 15, the depth of the charge. being regulated by bafiles 20. When the column is full, the charge in the hoppers 14 stops any further supply from the bunker. The rate of feed of the charge is controlled by the amount drawn ofl at-the outlet 15. By suitably arranging the retort heads 17, 18, 19, 1'? being the admission head of the retort column, 18 the heads connecting two retorts, and 19 the discharge head of the retort column, the charge material is so guided in the retorts assisted by the baffles 20, the constricted intake passages 4 and the retort intake 28, that the depth of the charge measures about 30 to mm. and leaves about 70 per cent of the sectional area of the retort free for the passage of the carbonization gases. The said gases are removed separately at 21 and 22 for the purposeof recovering gases of different composition, or are jointly withdrawn through the pipe 23 and led further away. The outlet 19 of the retort column terminates in a shaking conveying trough 25, preferably of the off-balance type, described in the Zeitschrift des Vereins deutscher Ingenieure, 1926, page 309, which conveys the carbonized product directly on issuing from the retorts into a main bunker 26 which may be emptied into the trucks 29. This off-balance con veyor induces a uniform discharge of the charge material from the retorts and thereby sets up a uniformly regulated rate of flow of the charge in the retorts and a continuous supply from the coal bunker.

In its passage through the several retort heads, the charge is turned over every time, so that an excellent low-temperature carbonizing effect is produced. The rate of flow of the charge is controlled by raising and lowering the shutter 27 on the jig conveyor 25. The closing of the retort columns at the intake and the-outlet is effected by the charge of coal itself.

It is not necessary. to carry the heating gas current on the counterflow principle against the direction of flow of the material to be carbonized, but the hot gas current may advantageously be carried in the same direction. This manner of working has the advantage of allowing the employment of the heating gases at higher temperatures as they first act on the retorts charged with cold materials. In this case the combustion chamber- 5, the gas burners 11 and the nozzles 12 are connected at 8 to the chamber 1.

In addition to low-temperature carbonization, the process is applicable to the heat treatment of solid substances in any way; for example for drying or coking wood, peat and the like.

What I claim is:

1. An apparatus for the heat-treatment of solid materials, in particular for the low-temperature carbonization of bituminous fuels, which comprises a plurality of externally heatable, superposed pipes communicably connected in series and in zig-zag formation by means of connecting members, each pipe being inclined at an angle with the next adjacent pipes and being at an acute angle with the horizontal and each connecting member being provided with a by-pass for leading gases from one pipe to the next adjacent pipe.

2. An apparatus for the heat-treatment of solid materials, in particular for the low-temperature carbonization of bituminous fuels, which comprises a plurality of externally heatable, superposed pipes communicably connected in series and in zig-zag formation by means of connecting members, each pipe being inclined at an angle with the next adjacent pipes and being at an acute angle with the horizontal, each connecting member being provided with a by-pass for leading gases from one pipe to the next adjacent pipe, and bafiles for regulating the depth of the material under treatment arranged in said connecting members.

3. An apparatus'for the heat-treatment of solid materials, in particular for the low-temperature carbonization of bituminous fuels, which comprises a plurality of externally heatable, superposed pipes communicably connected in series and in zig-zag formation by means of connecting members, each pipe being inclined at an angle with the next adjacent pipes and being at an acute angle with the horizontal, each connecting member being provided with a by-pass for leading gases from one pipe to the next adjacent pipe, and baflies for regulating the depth of the material under treatment arranged in said connecting members and in the pipes themselves.

4. An apparatus for heat-treating solid carbonaceous material to obtain gases therefrom comprising a plurality of externally heatable superposed pipes arranged in zig-zag formation, members, defining chambers, connecting the ends of said pipes in series relationship, each of said connecting members being provided with a bypass for leading gases from one pipe to the next adjacent pipe, each pipe being inclined at an angle with the next adjacent pipes and being at an acute angle with the horizontal, a passageway for the gases evolved from said material above said material thus being provided and means for feeding material into the upper end of the uppermost pipe and means for withdrawing material from the lower end of the lowermost pipe.

5. An apparatus for heat-treating solid carbonaceous material to obtain gases therefrom comprising a plurality of externally heatable, superposed pipes arranged in zig-zag formation, members, defining chambers, connecting the ends of said pipes in series relationship, restricted intakes on each pipe for directing the material to be treated from one pipe to the next adjacent pipe, each of said connecting members being provided with a by-pass for leading gases from one pipe to the next adjacent pipe, each pipe being inclined at an angle with the next adjacent pipes and being at an acute angle with the horizontal, means for feeding material into the first pipe of said series and means for withdrawing treated material from the last pipe.

6. A device as in claim 5 wherein bafiles are provided in said pipes and the chambers in said connecting members to regulate the height of material in said pipes. 

